The present invention relates to anti-theft devices for motor vehicles. In the past, anti-theft devices have been either highly concealed electronic devices or mechanical devices which are fully detachable after use. All of those prior art devices have the great disadvantages of allowing the concealment of tampering with the device. With the prior art anti-theft devices, a motor vehicle which has had its anti-theft device avoided in some manner may, nevertheless, be unobtrusively operated.